Improvement in sheet-metal cans



P. H. PALM-ER. Sheet-Metal Can.

No. 220,089. Patented Sept. 30,1879.

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B V a a.

fig. 2.

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[i J WITNESSES- J a INVENTDB 7 BY A ATTORNEY MPEI'ERS,FHOTO-LITHUGRAFHER. WASHXNGTON D G UNITED STATES PATENT OF -Ion.

FRANK H. PALMER, OF BROOKLYN, N, Y., ASSIGNOR TO F. O. PIERCE & GO.

IMPROVEMENT IN SHEET-METAL CANS.

Specification forming part of Letters Patent No. 220,089, datedSeptember 30, 1579; application filed August 19, 1879.

To all whom it may concern: Y

Be it known that I, FRANK H. PALMER, of Brooklyn, in the county of Kingsand State of New York, have invented certain new and useful Improvementsin Paint-Cans; and I do hereby declare the following to be a full,clear,

- and exact description of the invention, such as will enable othersskilled in the art to which it appertain's to make and use the same,reference being had to the accompanying drawin gs, and to letters ofreference marked there on, which form a part of this specification, inwhich- Figure 1 represents a side view of a can constructed according tomy improvement, having a part broken away; and Figs. 2 and 3, sectionalviews of modified forms of the rim and hem.

This invention relates to that class of cans in which the cover isunsoldered by a blow on its top.

It consists, mainly, in so constructing the can and its cover as to cutthe solder rather than tear it apart, and to prevent those surfaces ofthe cover and can that are in lapping contact from adhering together. Toaccomplish this I make my cover with a rim of reduced thickness at itsbottom to form a cuttingedge, and to prevent the soldering of thelapping surface, 1 leave one of them untinned but in order that thecover may be united airtight with the can I have the latter tinned onits outer surface, so that the exposed surfaces may be readily soldered.

In the accompanying drawings, A represents the body of the can, having aperfectly plain inside, and provided with a hem,a, of peculiar form.This hem may be made by turning over a double fold, as shown in Fig. 1,or a triple one, as in Fig. 3; or, if preferred, the hem may be made byturning a single fold of the tin over a strip of sheet metal or a wirering. This hem I prefer to make with its double or triple fold so formedthat at the top of the can there will be but two thicknesses of metalthat is to say, only the metal forming the can and one thickness of thefold-and at the bottom of the hem all the thicknesses of the metal willbe combined, so as to form a bulge or swell.

For very heavy cans four or live folds, or even more, may be used.

The lower edge of the fold should always be turned under or between thefirst fold and the body of the can, so that the metalvwill be continuousfrom the top of the can to the lower edge of the hem, to avoid leavingany crease that will prevent the edge of the cover passing onto thebulge of the hem, as would be the case were the lower fold of the hemturned outward or away from the. body of the can.

By this arrangement of the fold there will be formed a hem having itsupper portion either straight or slightly tapering, on which the coverwill fit tight, and a bulge or swell, against which the edge of thecover will rest, and to which the lid is soldered. In addition to thisthe hem makes the can much stronger than it would bewithout it, and thecan has the advantage of being smooth inside, which is not the case whencorrugations are formed on the body to strengthen it. With this can Iuse a cover, B, preferably made in one piece,

as in Figs. 1 and 2, but do not limit myself to this form, as it may bemade inthe old-fashioned way, with the top and rim in two pieces. Thiscover I usually make of plain untin'ned iron, drawing down the rim untilit has ash arp edge; but sometimes I make the rim of the ordinarythickness of the metal, and then bevel off the lower edge, as shown inFig. 2; or it may be beveled in the opposite direction, if preferred.

After the cover is formed I usually tin the outside only, although forspecial purposes I tin both sides, or sometimes I tin the outside andvarnish the inside, or coat it with some substance that will not affectthe cans contents.

If preferred, the cover may be formed of iron tinned on one side only;or the top may be made of ordinary tin and the rim of sheet iron tinnedonly on one side 5 or the cover may be made of ordinary sheet-tin, andthe interior surface of the rim be ground away, which will remove thetin and reduce the edge, bringing it to the form shown in Fig. 1; or thetin coating may be removed from the inside of the rim by acid. This canis to be filled and closed in the ordinary manner, and when properlysoldered is perfectly air-tight. It is, however,

more readily unfastened when desired than any other soldered can withwhich I am acquainted, because when the inside of the rim of the coveris left untinned, as I prefer it should be, the solder does not unitewith the untinned portion, aml the cover is only fastened to the body ofthe can by the line of solder at the junction of the cap with the swellof the hem, which is readily severed by holding the can a slightdistance from the floor, or from a bench, and allowing it to fall, coverside down, so as to strike the cover square on the floor or bench; or ablow from a mallet or a piece of board will sever the solder equally aswell. The concussion caused by such a blow or fall acting on the coverwill make the sharp edge of the cap cut the solder, and the can can thenbe readily opened. The bulge on the hem also assists by serving to forceopen the rim, and thus enlarge it, so that, without forming slits in therim, the cover may be readily removed when nnsoldered.

From this it will be seen that a can formed as described has theadvantages of perfect smoothness inside, so that its contents may bereadi y removed, extra strength caused by the peculiar formed hem, whichwill make it well adapted for shipping purposes; that there is no spacefor paint between the rim and the can; and that although perfectlyair-tight when soldered, yet it is readily opened by a slight blow, asthe solder is out instead of being torn, as in the old style of can, andwhen the inner side of the rim is untinned, as I prefer it to be, thereis little or no chance for it to become soldered fast to the can.

I do not limit myself to the use of the forms of hem here shown, asother hems may be used in connection with my cover, or cans withcorrugations instead of hems, or plain cans without corrugations orhems. Cans may also be made with strengthening wires or hands solderednear the top of the can in about the same position occupied by the bulgein the hem of my can, and with such cans coverslike mine may be readilyused, although I prefer the liems shown in my drawings.

I do not Wish to be understood as claiming the use of all kinds ofstrengthening hems, bands, or corrugations, as I am aware that manydevices of this kind have already been in use. I am also aware that ithas been proposed to make cans with heads of untinned iron and coat themwith tin on the outside after the head has been fastened to the body;that a patent has been granted for using a galvanized cover upon atinned-iron body, and that it has been proposed to tin the edges ofuntinned iron, that they might be readily soldered together. Theseplans, however, all differ from mine, and I make no claim to them.

What I claim as new is- 1. The combination, with a can, A, of a cover,B, having the bottom of its rim reduced in thickness to form acutting-edge, substantially as and for the purpose specified.

2. The combination, with a can, A, of a cover, B, having its rim beveledto form a cuttin g-edge, substantially as and for the purpose specified.

3. The combination of a can, A, and cover B, having one of their lappingsurfaces untinned to prevent said lapping surfaces being soldered, andthe exposed surface of the cover tinned, so that the tin coating of thecover may readily unite with the tin on the exposed portion of the body,substantially as and for the purpose specified.

4. A can-body provided with a hem, consisting of a straight orslightly-tapered portion above and a bulge or swell below, formed byturning down a fold of the metal and inclosing between said fold and thebody of the can one or more smaller folds, substantially as and for thepurpose specified.

In testimony that I claim the foregoing I have hereunto set my hand this12th day of August, 1879.

FRANK II. PALMER.

\Vitnesses:

EDWARD SELLECK, SAMI'EL SCIIUMACHER.

